Capture and label the current camera frame to compare before-and-after views later. Useful for judging camera moves or defining shots within a session.
Store the current picture under a label, so it can be compared later.
Useful before a move whose result you will judge later, or to establish what "the wide shot" looks like. Marks live in memory for this session only.
| Name | Required | Description | Default |
|---|---|---|---|
| label | Yes |
Changes observed during successful MCP inspections.
v0.1.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it does disclose one important trait: marks are ephemeral, 'live in memory for this session only'. It says nothing about overwrite behavior for a reused label, any cap on the number of marks, or whether the snapshot captures the framing/pose versus the rendered image.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three short sentences, front-loaded with the core action, followed by motivation and lifetime note. Every sentence contributes and none restate the name or the schema.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a one-parameter, no-output-schema tool the description covers purpose, typical triggers, and persistence scope, which is most of what an agent needs. It omits the label-collision/overwrite rule and how marks are later retrieved, which are the remaining gaps given no annotations exist to fill them.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0% for the single 'label' parameter, so the description must compensate. It reveals the label's role as the key used for later comparison, but gives no format, uniqueness, or length guidance; the agent still has to guess what makes a valid label.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description gives a concrete verb and object ('Store the current picture under a label') plus the reason it matters ('so it can be compared later'). An agent can distinguish this snapshot-taking tool from siblings like check_view, run_shot, or aim without inspecting any schema.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It states concrete contexts where the tool is appropriate: before a move whose result you will judge later, or to establish a known reference framing like 'the wide shot'. It does not name a sibling alternative (e.g. check_view for retrieval) or any when-not condition, so it stops short of a full routing rule.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.